Okay I just put a silencer on my 10mm pistol and when I equip it some big red thing that has a exclamation mark in the middle of it. What is it cuz it's annoying I dont want this big thing appearing when all I want is the mod.

Because you modded the unique Weathered 10mm pistol. Revert to an earlier save and apply the mod to a normal 10mm pistol.

If you have the weathered 10mm pistol from one of the pre orders, there is a known glitch when you add mods to it. Its not supposed to accept modifications but for some reason you can still add them it just causes a red exclamation mark. If this is what it is you'll have to reload a previous save to undo this.

Thanks. That's exactly what it is.